Use the maximum graph size in max_use_ratio

Instead of using current size of the graph, use the size the graph had at its largest. This enables optimizations like constant-folding to reduce greatly the total number of nodes in the graph without triggering an error.

Use the maximum graph size in max_use_ratio
e5216440 · Pascal Lamblin · 148a5819 · e5216440
--- a/theano/gof/opt.py
+++ b/theano/gof/opt.py
@@ -1113,6 +1113,7 @@ class EquilibriumOptimizer(NavigatorOptimizer):
        max_use_abort = False
        opt_name = None
        process_count = {}
+        max_nb_nodes = 0

        while changed and not max_use_abort:
            changed = False
@@ -1130,7 +1131,8 @@ class EquilibriumOptimizer(NavigatorOptimizer):

            q = deque(graph.io_toposort(env.inputs, start_from))

-            max_use = len(q) * self.max_use_ratio
+            max_nb_nodes = max(max_nb_nodes, len(q))
+            max_use = max_nb_nodes * self.max_use_ratio
            def importer(node):
                if node is not current_node:
                    q.append(node)